
    // 定义常量--根目录
    const BASE_URL="http://47.110.91.18:8084/book/book"
   function postPromise(url,params={},dataType="json"){
       return  new Promise((resolve)=>{
            $.ajax({
                url:BASE_URL+url,
                type:"post",
                dataType:dataType,
                data:params,
                success:function(data){
                    resolve(data);
                }
            });
        });
    }